1. Field of the Invention
This invention relates to a mode changing apparatus for a tape recorder, and more particularly is directed to improvements in a mode changing apparatus of the feather-touch push-button type.
2. Description of the Prior Art
In a tape recorder having a conventional mode changing apparatus of the feather-touch, push-button type, an electromagnet is employed for establishing each of the selected modes of operation, for example, for moving a head base plate or carriage from an inactive position to an active position in which the tape is engaged by a head or heads on the base plate and/or for displacement of a pinch roller to an operative position against an associated capstan for driving the tape therebetween during a recording or reproducing operation. Such electromagnet requires a current supply thereto during the entire recording or reproducing operation, that is, upon interruption of the current supply to the electromagnet, the head base plate or carriage is returned by a spring to its inactive position for spacing the head or heads from the tape and/or for separating the pinch roller from the capstan. Further, the electromagnet used in such conventional mode changing apparatus needs to be relatively large for maintaining the head base plate in its active position against the force of the return spring and, accordingly, such electromagnet imposes a disadvantageously large current drain which is not suited for a battery-powered tape recorder.
In order to avoid the foregoing problem, it has been proposed to provide a mode changing apparatus with an electromagnet which is only momentarily energized to effect a triggering action by which the torque of an electric motor is transmitted to a mechanism for changing the operating mode. In this last mentioned mode changing apparatus, the electromagnet is not energized during the entire recording or reproducing operation, thereby to minimize the current drain resulting therefrom. However, there is usually included an additional locking mechanism for securing the operating mode changing mechanism in the condition characteristic of the selected operating mode, whereby the structure is undesirably complex. Furthermore, the mentioned locking mechanism cannot be electrically released so that problems are encountered in resetting the mode changing apparatus, particularly by remote operation thereof.